• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.43 no.4 s.310
• /
• pp.123-132
• /
• 2006

In this paper, the digital video and audio system is improved so that various digital video data formats in DVD disc, and digital audio data formats through the S/PDIF ports may be decoded. It is not easy to implement all decoding functions of video and audio by a DVD processor. The special structure in audio decoding circuit is proposed in this system so as to have simultaneously almost same video and audio performance in quality. By dividing the decoding circuit separately into video and audio part, the audio quality can be dramatically improved together with supporting several audio formats and with several effects. In order to satisfy the perfect audio system to support to audio decoding formats, it is just enough to get the expensive, complicated decoder. However, it may be not easy to get this expensive decoder in near future. Therefore it is rather to adopt the downloading method by which the host should download the appropriate code into memory by detecting the corresponding audio bit streams. It is proved that this method may be efficient in the point of sharing resource of audio data for video decoding.

• Journal of Internet Computing and Services
• /
• v.10 no.5
• /
• pp.33-39
• /
• 2009

In this paper, the Window based dual-mode audio receiver of DAB and DAB+(Digital Audio Broadcasting Plus) is designed, and audio performance of it is analyzed. DAB+ can be composed of DAB and AAC(Advanced Audio Coding) for more effective audio services in the limited channel bandwidth. In the result of thesis, the Window based receiver can simultaneously be decoded for DAB/DAB+ dual-mode audio.

• The Journal of the Acoustical Society of Korea
• /
• v.32 no.4
• /
• pp.346-353
• /
• 2013

This paper deals with the implementation of a high-quality audio system for karaoke. For improving the key/tempo changes performance, we separated the audio into many musical instrument channels. By separating musical instrument channels, high-quality key/tempo changes can be achieved and we confirmed this using the cross-correlation distribution and the MOS evaluation. The improved audio system was implemented using the TMS320C6747 DSP with fixed/floating-point operations. The implemented audio system can perform the multi-channel WMA decoding, the MP3 encoding/decoding, the wav playing, the EQ, and the key/tempo changes in real time. The WMA channels used for processing the separated instrument channels. The audio system includs the MP3 encoding/decoding function for playing and recording and the wav channel for the effect sound.

• Proceedings of the IEEK Conference
• /
• 2006.06a
• /
• pp.369-370
• /
• 2006

This paper presents a new method for Huffman decoding specially designed for the MPEG-2 AAC audio. The method significantly enhances the processing efficiency of the conventional Huffman decoding realized with the ordinary binary tree search method. A data structure is newly designed based on the numerical interpretation of the incoming bit stream and its utilization for the offset oriented nodes allocation. The experimental results show the average performance enhancement of 54% and 665%, compared to those of the conventional binary tree search method and the sequential search method, respectively.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.44 no.5
• /
• pp.112-117
• /
• 2007

This paper presents specialized DSP instructions and their hardware architecture for audio coding algorithms, such as the MPEG-2/4 Advanced Audio Coding(AAC), Dolby AC-3, MPEG-2 Backward Compatible(BC), etc. The proposed architecture is specially designed and optimized for the MDCT/IMDCT(Inverse Modified Discrete Cosine Transform), and Huffman decoding of the AAC decoding algorithm. Performance comparisons show a significant improvement compared with TMS320C62x and ASDSP21060 for the MDCT/IMDCT computation. In addition, the dedicated Huffman decoding accelerator performs decoding and preparing operand in only one cycle. The proposed DPU(Data Processing Unit) consists of 107,860 gates and achieves 150 MIPS.

• Journal of the Korean Institute of Telematics and Electronics A
• /
• v.30A no.3
• /
• pp.16-33
• /
• 1993

New decoding algorithm of double-error-correction Reed-Solmon codes over GF(2$^{8}$) for optical compact disks is proposed and decoding algorithm of RS codes with triple-error-correcting capability is presented in this paper. First of all. efficient algorithms for estimating the number of errors in the received code words are presented. The most complex circuits in the RS decoder are parts for soving the error-location numbers from error-location polynomial, so the complexity of those circuits has a great influence on overall decoder complexity. One of the most known algorithm for searching the error-location number is Chien's method, in which all the elements of GF(2$^{m}$) are substituted into the error-location polynomial and the error-location number can be found as the elements satisfying the error-location polynomial. But Chien's scheme needs another 1 frame delay in the decoder, which reduces decoding speed as well as require more stroage circuits for the received ocode symbols. The ther is Polkinghorn method, in which the roots can be resolved directly by solving the error-location polynomial. Bur this method needs additional ROM (readonly memory) for storing tthe roots of the all possible coefficients of error-location polynomial or much more complex cicuit. Simple, efficient, and high speed method for solving the error-location number and decoding algorithm of double-error correction RS codes which reudce considerably the complexity of decoder are proposed by using Hilbert theorems in this paper. And the performance of the proposed decoding algorithm is compared with that of conventional decoding algorithms. As a result of comparison, the proposed decoding algorithm is superior to the conventional decoding algorithm with respect to decoding delay and decoder complexity. And decoding algorithm of RS codes with triple-error-correcting capability is presented, which is suitable for error-correction in digital audio tape, also.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.46 no.5
• /
• pp.151-161
• /
• 2009

Audio Video Standard (AVS) is the audio and video compression standard that was developed for domestic video applications in China. AVS employs low complexity tools to minimize degradation of RD performance of the state-the-art video codec, H.264/AVC. The AVS video codec consists of $8{\times}8$ block prediction and the same size transform to improve compression efficiency for VGA and higher resolution sequences. Currently, the AVS has been adopted more and more for IPTV services and mobile applications in China. So, many consumer electronics companies and multimedia-related laboratories have been developing applications and chips for the AVS. In this paper, we implemented the AVS video decoder and optimize it on TI's Davinci EVM DSP board. For improving the decoding speed and clocks, we removed unnecessary memory operations and we also used high-speed VLD algorithm, linear assembly, intrinsic functions and so forth. Test results show that decoding speed of the optimized decoder is $5{\sim}7$ times faster than that of the reference software (RM 5.2J).

• Proceedings of the KIEE Conference
• /
• 2006.10c
• /
• pp.428-430
• /
• 2006

This paper proposes a new means of performance optimization for multimedia algorithm utilizing the Microscopic DVS (Dynamic Voltage Scaling). The Microscopic DVS technique controls the operating frequency and the supply voltage levels dynamically according to the processing requirement for each frame of multimedia data. The huffman decoding algorithm of MPEG-2 AAC audio decoder is optimized to maximize the power saving efficiency of Microscopic DVS technique. The experimental results show the reduction of computational complexity by more than 30% and the reduction of power consumption by more than 17% compared with those of the conventionally fast method.

• The Transactions of the Korean Institute of Electrical Engineers D
• /
• v.55 no.12
• /
• pp.544-546
• /
• 2006

This paper proposes a new means of performance optimization for multimedia algorithm utilizing the Microscopic DVS (Dynamic Voltage Scaling). The Microscopic DVS technique controls the operating frequency and the supply voltage levels dynamically according to the processing requirement for each frame of multimedia data. The huffman decoding algorithm of MPEG-2 AAC audio decoder is optimized to maximize the power saving efficiency of Microscopic DVS technique. The experimental results show the reduction of computational complexity by more than 30% and the reduction of power consumption by more than 17% compared with those of the conventionally fast method.

• Proceedings of the IEEK Conference
• /
• 2005.11a
• /
• pp.945-948
• /
• 2005

In wireless and handheld platforms area, performance, power and cost are key metrics for product success. This is driving increasing levels of on-chip integration in state-of-the-art application processors. The purpose of this project is to optimize and design the energy-efficient embedded system that properly displays video and audio in real time. The requirements are for the media player to be capable of decoding real-time streaming video and audio with the least possible energy consumption for a variety of different clips at different resolutions. We implemented this Linux based multimedia player on Intel's PXA27x platform.